Forming method of thermal insulation film and internal combustion engine

Patent metadata

Field	Value
Publication number	US-10385772-B2
Application number	US-201514974291-A
Country	US
Kind code	B2
Filing date	Dec 18, 2015
Priority date	Dec 26, 2014
Publication date	Aug 20, 2019
Grant date	Aug 20, 2019

Abstract

A forming method of a thermal insulation film includes a first step of forming an anode oxidation coating film on an aluminum-based wall surface, the anode oxidation coating film including micro-pores each having a diameter of micrometer-scale and nano-pores each having a diameter of nanometer-scale; and a second step of coating a surface of the anode oxidation coating film with a sealant containing filler to seal at least part of the micro-pores and the nano-pores by the sealant so as to form the thermal insulation film.

First claim

What is claimed is:

1. An internal combustion engine in which a portion or all of aluminum-based wall surfaces of a combustion chamber is formed with an anode oxidation coating film, wherein:
the anode oxidation coating film includes first micro-pores each having a diameter of micrometer-scale and nano-pores each having a diameter of nanometer-scale that extend inwardly in a thickness direction or approximately in the thickness direction of the anode oxidation coating film from a surface of the anode oxidation coating film, and second micro-pores located inside the anode oxidation coating film and each having a diameter of micrometer-scale;
at least part of the first micro-pores and the nano-pores are sealed by a seal containing filler particles, the seal being converted by a sealant containing the filler particles, and at least part of the second micro-pores are not sealed;
the filler particles have a size from 10 to 100 nm;
the filler particles are present in at least some of the sealed nano-pores; and
a surface roughness Ra of the anode oxidation coating film is from 1.51 to 4.49.

2. The internal combustion engine according to claim 1 , wherein the sealant and the seal are formed by material having silicon as a main constituent.

3. The internal combustion engine according to claim 1 , wherein the sealant and the seal are formed by any one of polysiloxane or polysilazane.

4. The internal combustion engine according to claim 1 , wherein the filler particles are made of a material selected from the group consisting of silicon, alumina, boron nitride, silicon nitride, silicon carbide and magnesium oxide.

5. The internal combustion engine according to claim 4 , wherein the sealant and the seal are formed by any one of polysiloxane or polysilazane.

6. The internal combustion engine according to claim 1 , wherein the diameter of the nano-pores is from 10 to 100 nm.

7. The internal combustion engine according to claim 1 , wherein the size of the filler particles is from 10 to 15 nm.

8. The internal combustion engine according to claim 1 , wherein the size of the filler particles is from 40 to 50 nm.

9. The internal combustion engine according to claim 1 , wherein the size of the filler particles is from 70 to 100 nm.

10. The internal combustion engine according to claim 1 , wherein the filler particles are made of silicon dioxide.

11. The internal combustion engine according to claim 1 , wherein the surface roughness Ra of the anode oxidation coating film is from 1.51 to 1.74.

12. The internal combustion engine according to claim 1 , wherein the surface roughness Ra of the anode oxidation coating film is from 1.51 to 3.58.

Assignees

• Toyota Motor Co Ltd
• Toyota Chuo Kenkyusho Kk

Inventors

• Takagishi Reona
• Nishikawa Naoki
• Tani Masaaki
• Horie Toshio
• Shimizu Fumio
• Hohjo Hiroshi
• Wakisaka Yoshifumi
• Murase Masakazu

Classifications

• F01L3/04

  Coated valve members or valve-seats · CPC title

• F02B77/02 Primary

  Surface coverings of combustion-gas-swept parts (of pistons F02F3/10; of cylinders and cylinder heads F02F1/00) · CPC title

• C23C18/1212

  Zeolites, glasses · CPC title

• C23C18/1245

  Inorganic substrates other than metallic · CPC title

• C25D11/246 Primary

  for sealing layers · CPC title